As the digital age progresses, the use of electronic transmission and storage of data has become the norm for many users. Particularly in electronic communications, email has played an ever-increasing role. However, without proper security and privacy measures, this increased importance of email can lead to severe consequences. An information security infrastructure can be useful in providing the confidentiality, integrity and availability of information, which are the main concerns of many individuals as well as entities such as businesses, universities, hospitals, and so on who have a greater need for secure data transmission, storage and maintenance.
Currently, Public Key Infrastructure (PKI) systems enable users to exchange data securely and privately over a network such as the Internet or an intranet through the use of a public and a private cryptographic key pair that may be obtained and shared through a trusted third party authority. The public key cryptography, also known as asymmetric cryptography, is perhaps the most common method on the Internet for authenticating a message sender or encrypting a message. A PKI system has the following features:                One or more trusted third party certificate authorities (CAs)—a CA is an organization that issues digital certificates;        Digital certificates—these are electronic credentials, each of which identifies an individual or an organization and which includes the public key or information about the public key;        One or more registration authorities (RAs)—an RA is an entity that is responsible for identification and authentication of digital certificates but does not sign or issue digital certificates as it is delegated with certain tasks on behalf of an authorized CA;        One or more directory services that can store and, when necessary, revoke the digital certificates; and        A certificate management system.        
In the public key cryptography, a public key and a private key are created simultaneously using the same algorithm provided by a CA. The public key is made publicly available as part of a digital certificate in a directory that all parties can access. The private key is not meant to be shared with anyone or sent across an unsecured network such as the Internet.
As an example, User A can obtain (from User B, a public directory, a network administrator, etc.) User B's public key, encrypt a message using User B's public key, and sends User B the encrypted message over an unsecured network. When User B receives the encrypted message, User B can decrypt the encrypted message using his private key which was created with the public key used by User A to encrypt the message. In addition to encrypting messages to ensure privacy, User A can authenticate herself by using her private key to encrypt a digital certificate or signature. When User B receives the digital certificate, User B can decrypt the encrypted digital certificate using User A's public key. This proves to User B the identity of the sender (i.e., User A).
Despite the benefits provided by electronic communications systems and methods, and more particularly communications systems which rely on PKI, room for improved systems and methods of secure communication exists.